Abstract
The compounds RENi4 Mg have been elaborated by mechanical alloying (MA) and a subsequent heat treatment at 600 {ring operator} C for 1 h. The lattice parameters are in good agreement with those already reported: 7.165 over(A, ̊) for LaNi4 Mg, 7.030 Å for CeNi4 Mg and 7.038 over(A, ̊) for GdNi4 Mg. The hydrogen sorption behaviors are strongly influenced by the rare earth used: for La compound, hydrogen absorption leads to a structural change and no desorption can be observed, for Ce compound, no reaction towards hydrogen can be noticed and for Gd compound, hydrogen can be absorbed and desorbed reversibly at room temperature. Moreover, for GdNi4 Mg, no structural change is reported after hydrogenation and only a slight volume expansion can be noticed (e.g. 5%). The MA process has also been used successfully for the elaboration of GdNi4 - x Alx Mg up to x = 1. In these substituted compounds, hydrogen can also be absorbed and desorbed reversibly at room temperature.
Original language | English |
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Pages (from-to) | 2422-2428 |
Number of pages | 7 |
Journal | International Journal of Hydrogen Energy |
Volume | 32 |
Issue number | 13 |
DOIs | |
Publication status | Published - Sep 2007 |
Externally published | Yes |
All Science Journal Classification (ASJC) codes
- Renewable Energy, Sustainability and the Environment
- Fuel Technology
- Condensed Matter Physics
- Energy Engineering and Power Technology